Burring machine



51. ABRADxNG.

Sept. 4, 1945. G. GERUNG BURRING MACHINE Filed April 8, 1944 Exammer Patented Sept. 4, 1945 Examine:

UNITED STATES PATENT OFFICE 2 Claims.

This invention refers to abrasive machinery and more particularly to one so-called burring machine for removing burrs and unevenness at holes drilled or punched in materials and particularly those of sheetI metal. It has among its objects to provide a machine of this type that will be capable of handling a sheet of material having many holes drilled or punched in it, so that they may all be cleaned of burrs simultaneously in one machine operated by power. 'Ihis object includes the use of the machine over a large area of material. Another object is to have the machine capable of doing its work on both sides of a sheet of material at the same time. A further object is to design the machine so its motion or operation will not tend to displace the material to an objectionable degree. Still another is to adapt the machine so it will be capable of doing its work speedily and effectively, and its operati-cn handled by relatively unskilled labor.

Other objects Awill become apparent as the invention is more fully set forth.

The usual manner of removing burrs from material, such as metal wings of aeroplanes, etc., at the holes that are drilled or punched through same, is by ling or the use of a sander requiring the skilled services of an operator manually operating such a device in one of his hands, or the use of a' file or counterboring machine. This is laborious and limits the capacity of work to be accomplished by an operator.

In this invention, a machine of convenient size is capable of doing the work of thirty operators, and with more eiective results in a fractional part of the time. It consists in general of a sander or other abrasive attached to frames that oscillate on the upper and underneath surfaces of a plate of material so as to engage and remove the burrs left at the hole openings after drilling or punching.

In the drawing which is used to illustrate a machine embodying this invention:

Figure 1 is a plan view of a burring machine operating on a sheet of material and embodying this invention;

Figure 2 is a sectional side elevation taken along line 2--2 of Figure 1;

Figure 3 is a side elevation of Figure l, and

Figure 4 is a sectional end elevation of the machine looking in the direction of the arrows 4-4 of Figure 3.

Similar reference characters refer to similar parts throughout the drawing.

In the drawing, I represents a base on which the machine is supported and operated from. This base is intended to rest on the iloor of a room, and form the locus from which the motor 2, and other motive mechanisms operate the upper sander tables 4 and 5; and the underneath tables 6 and 1, respectively. The tables reciprocate while in operation and hold a sheet or plate of material I5 having drilled or punched holes 41, between them as indicated in the drawing. The tables have curved operating faces 8, 9, III and I I respectively, which become flat when contacting the faces of the plate material. The faces are covered with sandpaper or other flexible abrasive I2, that face towards each other and contact the upper and lower surfaces I3 and Il of the material I5 respectively. The tables are preferably spaced from each other transversely, and are reciprocated by crank Il through the crank pins I6 and links I'I. When the upper pair of tables operate, they move towards each other as a part of the stroke and away from each other during the rest of the stroke, in a horizontal plane. At the same time, the underneath tables work similarly through the rotating of the crank I8 and the action of the links I1 and pins I6. The arrows indicate the operation of the tables during one portion of the stroke. 'Ihe upper table at one side and its table underneath operate in the same direction at the same time. In the same way, the pair of tables on the other side likewise operate.

Any conventional method of fastening the abrasive material to the tables may be used, but in the drawing, clamping arrangement I9 and adjustable screw devices 20 are utilized to give the necessary tension and tightness, flexible material 2l under the flexible abrasive material I2 allows the abrasive material to adjust itself to suit contour of the face of the sheet.

The motors 2 operate the shaft 22 on which the cranks I8 are mounted through a transmission 23. Details for the control of the motors are not shown, as it is presumed that such are well known, and do not need explanation or further description.

The tables are made in rectangular frame form as indicated.

I'he'links I'I connect with the lugs 24 on the tables and are arranged to give any desirable flexibility to the links and facility to the operation.

In the operation of the device, the sheet of holed material I 5 is fed through rollers 25 onto the lower pair of tables in a horizontal position. The lower tables are then adjusted on their adjusting screws 26 by raising them until the faces I3 and I4 of the material I5 are contacted. The lower tables are then locked in such position through the use of the bolts 21 used for tightening same in the elongated slots 28. 'I'he underneath tables are established at their proper position and are supported and guided on the auxiliary frame 30 supported on the base. The grooves 3l in the frame and the runners 32 on the tables 6 and 1 serve to hold the latter in position. The upper sander tables 4 and 5 are guided in grooves 33 through the use of their runners 34. The tables at each end rst travel towards the middle and their sanders I2 slide across the face of the sheet plate I5, rubbing up across the burrs 35 and abrading same. The plate stays still during the operation because it is acted on under compression. The tables then move back across the plate and put the latter under tension, rubbing the burrs in the opposite direction and smoothing them olf. This continues for such time as may be necessary. This is an oscillating motion and is preferably done at the rate of 2000 to 3000 times a minute. The stroke is preferably a little under three inches. With pressure not excessive, the sanders will do their work effectively in a short period of time. The actual length of time depends on the material being abraded. The type of frame used as a base and auxiliary support for the tables to run in are preferably as shown in the drawing, with the grooves therein for the runners of the tables made sui-table for the work to be done,

' and with lubrication and other details, usually While but one general form oi' the invention is shown in the drawing and described in the speciilcation, it is not desired to limit this application for patent to this particular form or in any other way otherwise than limited by the scope thereof, as it is appreciated that other forms of construction could be made that would use the same principles and come within scope of the appended claims.

Having thus described the invention what is claimed is:

1. A sheet burrlng machine of the class described, comprising in combination. upright members forming a base, upper grooved members attached to said uprights in a horizontal manner, lower horizontal grooved members adjustably attached to said uprights, C shaped sanding units operating in said grooves in a reciprocating manner, cushioned abrasive material attached to said sanding units, reciprocating means attached to said C shaped sanding units for moving the C units towards each other at the center of the sheet and away from each other towards the ends of the sheet, and power means for operating said reciprocating means.

2. A sheet burring machine of the class described comprising in combination, upright members forming a b ase, upper horizontal grooved members attached to said uprights, lower horizontal grooved members adiustably attached to said uprights, C shaped sanding umts comprising adjustably connected parallel plates, abrasive material attached to said plates, said C unit operating in said grooves in a reciprocating manner, a second C shaped sanding unit comprising adjustably connected parallel plates and abrasive material attached to said parallel plates, and operating in same grooves in a reciprocating manner towards and away from each other to remove burrs from sheet material, and means for operating the C shaped sanding units substantially as described.

GEORGE GERUNG. 

